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THE ANATOMY OF INSECTS 49
like substances employed in oviposition as an investment or attachment of the
eggs and for the construction o( the ootheca. They are especially well developed
in the ORTHOPTERA, MANTODEA, and BLATTARIA which produce large
oothecre and to a lesser degree in the LEPIDOPTERA and some other orders.
Bursa copulatrix or copulatory pouch. - "This may 01' may not be present in
insects although technically speaking the portion of the female reproductive
system which receives the spermatozoa from the male at the time of copulation
could be so designated; however, the term is restricted to modifications of the
tract for this specific purpose. Thus, in the honeybee, the distal end of the
vagina is distended for this purpose. The most pronounced modification, however,
is in the LEPIDOPTERA, where a special copulatory opening distinct
from thc vaginal opening is prcsent leading into a flaccis pouch, the bursa copulatrix.
This nonmuscular pouch is connected externally with the vagina by a
slender tube. The spermatozoa, deposited in the bursa copulatrix, propel
themselves up the connecting tube to the vagina and thence into the spermathecal
duct and the spermatheca" (Freeborn).
Oviposz'ior or egg-laying organ. - This is a specialized terminal mechanism
of frequent occurrence among insects which enables them to deposit eggs in
places suitable for their protection and development, such as holes in ground,
wood, leaves, fruits, and seeds, as well as on or in the eggs, larvre, pupre, and
adults of other insects and also in certain related animals. It usually consists
of three pairs of closely fitting unsegmented styles which serve not only as a
drill for excavating a cavity but also as a tube for inserting the eggs. It varies
in length from a small fraction of the length of the body to several times its
total length. In bees and wasps the ovipositor has been modified into a sting.
MALE REPRODUCTIVE ORGANS
Gonads. - The male gonads are paired testes which are situated above. below.
or beside the alimentary tract. As they are usually supported by the surrounding
tissues, suspensory filaments are poorly developed or entirely absent.
Each testis is a closed capsule that is divided into a series of follicles, chambers,
or testicular tubes in whose walls are the follicles in which are located the germ
cells that develop into the spermatozoa. The testes are of many types in the
various insects. In the primitive APTERYGOTA they are similar in size and
form to the ovaries, but in the more specialized PTERYGOTA they are much
smaller than the ovaries of the female of a like species.
Follicles. - These organs vary greatly in form and organization among insects.
Each consists of a simple enlarged chamber or sac in most APTERY­
GOT A, 01' it may appear as three 01' four bilobed chambers. The follicles are
small single chambers in NEUROPTERA and DIPTERA, two-chambered in
certain ANOPLURA, and include numerous globular or tubular organs in
ORTHOPTERA. Each follicle may be joined to the vasa deferentia by a slender
tube (vas ef/erens) as in ANOPLURA and some COLEOPTERA, or the testes
may be wholly enveloped in a common pigmented coat known as the scrotum.
Innumerable other intricate arrangements are found in various insects.